Mosfet with raised source and drain regions

摘要

A semiconductor substrate having a surface, a field oxide region at the surface and a gate structure above the surface are provided. A sidewall spacer is formed adjacent to the gate structure and a polysilicon layer is formed above the substrate, the polysilicon layer having raised first and second portions above the gate structure and field oxide region, respectively. A masking layer is formed above the polysilicon layer and then blanket etched to expose the raised first and second portions of the polysilicon layer which are subsequently removed to form a raised source/drain region from the polysilicon layer. Since the raised source/drain region is fabricated without using photolithography, high density MOSFETs are readily fabricated.